Also could be worth looking at Ducattis they mainly use 2 x 50mm Weber-Marelli throttle barrels, some run twin injectors too. A few of the racers ran triple injectors, two into the body and a 'shower' type like the Track/kick. That could help with your fuel supply problems. While on that train of thought, Wildgoody have you thought about adding a 2nd injector to the stock manifold?

WILDGOODY, I just watched hotrod tv or Horsepowertv, something to do with a blown mustang... anyways, there is a fuel management device that changes fuel pressure 10 psi for every pound of boost, but should be able to make it fit your application, where your rig would run stock fi untill yoou get under boost, then as the fuel pressure goes up with boost, your computer would not have to work so hard to keep everything working.  Know what I mean?  Not have to run high psi for daily driving.

Well adding a second injector would require a second
throttle body, I did have a supplimental injector but
it was not computer controlled so it was like driving a
a dirt bike on the street, when that injector opened up
wow look out, and fuel milage suffered greatly.

As far as the coolant, I don't know what Suzuki had in mind
but the intake manifold is the exit for all of the coolant that
goes to the radiator, I wouldn't worry about a small passage
that was just for heating the intake, also the intake houses
the thermostat, so it's a big rework, it might be easier to just
swap the head to a 16V and have the stock intake with MPI
injectors, but then I'm back to reworking the turbo header
and all the plumbing, which I want to do some day, but I'm
afraid I'll get it apart and not finished for Moab and Tierra Del Sol.
Mar and April are coming fast and I got more mods to do.

The adjustable PSI senceing fuel regulator is a help, but I'm allready
at more than double the stock pressure, in fact nearly triple, so an
extra 10 PSI over stock is not enough, those regulators work well
to keep the system pressure constant to the pressures in the intake
tract, but I'm still running short on fuel to keep things constant.

Thanks Rhino for the kick in the butt, I forgot to take in to
consideration the Sq mm of the throttle plates, I went in my
head somthing like 4x20 = 80 mm  DUH, LOL circles don't
work like that, OK so if I want to work on a trick throttle body
with 4 butterflys what is your oppinion on size 45mm ea
again do you think I would lose low end or would 35-40mm
be better suited for offroad. I guess I could make it bigger
and sleeve it should the low end turn to poo. Ohh and sorry
to hear about your laptop, I got one I need to work on so I
can travel with the MegaSquirt and tune as I drive, my other
option is to pack the desktop and run a voltage inverter LOL
isn't that a site in your mind.

I think you should use a MAF and a narrow band O2 for your
computer, did you want to turbo too ?? I can't remember but if
you do a MAP would also help to meter the A\F Ratio all 3 of
these should give you plenty of info to feed your computer,
MAF gives volume of air, MAP would give you engine load,
O2 to let the computer see whats happening and a RPM feed
to pulse the injectors, from these inputs you should be able to
build a very effective system, of coarse you need water temp
and air temp too these would help the computer do it's fine
tuning, you might also have an altitude sensor if you got nothing
else to do LOL, PITA at first, but it will be awsome when it's done.

Darrin

 

hello i come from france and i find ZUKIWORLD 2 month ago it's a very good site congretulation

running 4x45mm butterflies should not be a problem, supposed to greatly increase low end torque, I dont know about top end....  You would be better off installing 4 large injectors  into the runners which also gives better fuel delivery, which equals more power.  Get an injector driver.  Basically a large amplifier circuit that takes your single injector voltage and amplifies it to drive the four larger injectors so you wont cook your ecm.

If I were to drive 4 injectors I would be using the
MegaSquirt Computer too, it is designed to run 2
to 16 injectors, so I don't think there would be a
problem there. The MS computer is a batchfire
system and has 2 channels for injector activation.

Wild, Ive got a stock 8v manifold and I was thinking that you could weld bungs on the top of each runner for individual injectors. With the megasquirt system that would solve your fuel problem.

Later,
Bill

Ya that was my plan, then Rhino mentioned the small
Dia. throttle butterfly, and I began thinking. If I match
the intake port size to a set of 4x ??mm throttle plates
what kind of HP could I pickup, heck even a dual stock
size (45mm) throttle bodys or some other setup might
be a big improvement over just stock forced induction.

I have never found another TBI to work with so Fabbing
a new 4 butterfly setup is another option.